1. Field
The present disclosure relates to a robot cleaner and a wheel assembly.
2. Background
The robot cleaner includes a body defining an outer appearance. The body includes a plurality of wheels for movement of the body, a plurality of motors for rotating the plurality of wheels, respectively, and a control unit that controls the plurality of motors.
Further, the body may include an auxiliary wheel that helps the movement of the body, and a floor detection sensor that detects a state of a bottom surface.
The floor detection sensor may detect the state of the bottom surface. That is, the floor detection sensor may detect a lower area than a surface to be cleaned and a higher area (for example, a door sill or the like) than the surface to be cleaned.
When the floor detection sensor detects the lower area than the surface to be cleaned, the control unit controls the motors such that the body is moved rearward. On the other hand, when the floor detection sensor detects the higher area than the surface to be cleaned, the control unit controls the motors such that the body is continuously moved forward.
However, as an example, when a height of an obstacle such as the door sill, which is located at a particular height, is large, a problem that the wheels of the body cannot climb up the obstacle occurs. In this case, because the motors are continuously rotated in a state in which the wheels are caught by the obstacle, a problem that the wheels are damaged or the motors are overloaded occurs.
To solve the above problems, a robot cleaner including an auxiliary moving device having a movable member that lifts up a body is disclosed in Korean patent No. 10-1411742 (filed on Jun. 18, 2014) as the prior art document.
In case of the robot cleaner, as the body is lifted up by the auxiliary moving device, the robot cleaner may climb up an obstacle such as a door sill. However, because the auxiliary moving device should be additionally designed and applied, there is a problem in that a structure of the robot cleaner is complex and manufacturing costs thereof are increased.
Further, in case of the robot cleaner disclosed in the prior art document, the body is merely lifted up when the robot cleaner is moved forward. Thus, there is a problem in that it is difficult for the robot cleaner to climb up the obstacle such as the door sill when the body is moved rearward.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.